This patent document relates to the field of computer security, and, in particular, to the physical security of information presented on a computer display.
Data stored on and used by computer applications is often sensitive or confidential in nature. Sensitive information, such as corporate intelligence, financial data, health data and classified information are all commonly stored on and manipulated by computers. While it is widely recognized that such data must be kept secure from hackers who may attempt to access it via a computer network, it is less widely realized that such data must also be secure from casual or accidental disclosure when it is being displayed on a computer screen.
Consider the case of a computer in a doctor's office displaying individual medical data which must be secured under the HIPAA regulations. Such data may be open to casual disclosure to other patients walking through the office. It is well known that the likelihood of disclosure of sensitive data from casual viewing of a computer screen may be reduced by the use of a privacy filter, which reduces the angle from which a computer screen may be viewed, such that the screen may only be view from a head-on angle. In addition, it is also well known to use automatic screen savers, which typically black the screen or replace the data on the screen with an alternative graphic when the computer has not been used for a period of time. The screen saver, however, still does not prevent the viewing of data when there is an active user.
It would therefore be desirable to provide a way to limit the ability to view data on a computer display to a particular, authorized individual, regardless of whether or not the display is visible to casual passers-by.